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The total number of ways of selecting tw...

The total number of ways of selecting two numbers from the set `{1,,23,4,3n}` so that their sum is divisible by 3 is equal to a. `(2n^2-n)/2` b. `(3n^2-n)/2` c. `2n^2-n` d. `3n^2-n`

A

`(3n^(2)-n)/(2)`

B

`2n^(2)-n`

C

`(2n^(2)-n)/(2)`

D

`3n^(2)-n`

Text Solution

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The correct Answer is:
A
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